package cn.readjava.service;

import cn.readjava.bean.Permission;
import org.apache.shiro.spring.web.ShiroFilterFactoryBean;
import org.apache.shiro.web.filter.mgt.DefaultFilterChainManager;
import org.apache.shiro.web.filter.mgt.PathMatchingFilterChainResolver;
import org.apache.shiro.web.servlet.AbstractShiroFilter;

import javax.annotation.Resource;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

@Resource
public class ShiroService {

    @Resource
    private ShiroFilterFactoryBean shiroFilterFactoryBean;
    @Resource
    private PermissionService permissionService;

    /**
     * 初始化权限
     */
    public Map<String, String> loadFilterChainDefinitions() {

        // 权限控制map.从数据库获取
        Map<String, String> filterChainDefinitionMap = new LinkedHashMap<>();
        List<Permission> permissionList = permissionService.findAll();
        if (permissionList != null) {
            for (Permission permission : permissionList) {
                filterChainDefinitionMap.put(permission.getPermissionUrl(), "perms[" + permission.getPermissionName() + "]");
                System.out.println("加载权限：" + permission.getPermissionName() + "，通配路径：" + permission.getPermissionUrl());
            }
        }
        return filterChainDefinitionMap;
    }

    /**
     * 重新加载权限
     */
    public void updatePermission() {

        synchronized (shiroFilterFactoryBean) {

            AbstractShiroFilter shiroFilter = null;
            try {
                shiroFilter = (AbstractShiroFilter) shiroFilterFactoryBean.getObject();
            } catch (Exception e) {
                throw new RuntimeException("从ShirofilterFactoryBean错误中获取Shirofilter！");
            }
            PathMatchingFilterChainResolver filterChainResolver = (PathMatchingFilterChainResolver) shiroFilter
                    .getFilterChainResolver();
            DefaultFilterChainManager manager = (DefaultFilterChainManager) filterChainResolver
                    .getFilterChainManager();

            // 清空老的权限控制
            manager.getFilterChains().clear();
            shiroFilterFactoryBean.getFilterChainDefinitionMap().clear();
            shiroFilterFactoryBean.setFilterChainDefinitionMap(loadFilterChainDefinitions());
            // 重新构建生成
            Map<String, String> chains = shiroFilterFactoryBean.getFilterChainDefinitionMap();
            for (Map.Entry<String, String> entry : chains.entrySet()) {
                String url = entry.getKey();
                String chainDefinition = entry.getValue().trim().replace(" ", "");
                manager.createChain(url, chainDefinition);
            }

            System.out.println("更新权限成功！！");
        }
    }
}
